The present invention relates generally to breast pumps, and more particularly to a breast interface assembly for connecting a breast pump to a nipple of a breast.
Breast milk pumps are well known in the art. Breast milk pumps generally have a breast shield (also known as a suction hood), a connector, and a suction/vacuum device. The breast shield has a generally—conical shape and a central stem, much like a funnel, and is usually made of a transparent plastic, to allow the user to ensure proper fitting. The conical portion fits over a portion of the breast, while the nipple fits tightly into the central stem. Milk is extracted by rapidly changing the pressure within the central region in a cyclic manner, drawing the nipple towards the connector each time the pressure is reduced in a process known medically as “the milk ejection response”. The pressure may be altered manually, by pulling or squeezing a handle, or electrically, by connecting up to a vacuum pump and intermittently alternating the pressure; ideally, at a rate of between thirty and sixty cycles per minute. Expressed breast milk (EBM) drains from the breast shield into the milk port, flowing down a length of tubing in most cases.
Various attempts have been made to improve upon the first breast pump of 1854 and subsequent improvements to it. In an attempt to offer a product that fits every nursing mother perfectly, breast milk pumps come with a variety of sizes of breast shields. Variations in breast shield size tend to be in the size of the tubular end, which typically comes in the range of between 24 mm and 36 mm, but also includes a variety of sizes of the conical end. For example, U.S. Pat. No. 6,723,066 to Larsson et al. and titled “Breastpump with Universal Hood Base and Interchangeable Suction Hoods” describes a common suction hood base that can be used with a number of different sized shields. U.S. Pat. No. 4,857,051 to Larsson and titled “Breastpump” describes several ideas including an adjustment piece for decreasing the cross-sectional area of a funnel-shaped hood member. The hood member is another name for a breast shield. In this patent, a smaller-sized funnel is fitted inside a regular funnel-shaped breast shield to improve the fitting for smaller breasts.
Commercially, a breast pump is sold with a selection of breast shields that have similar sized conical ends, while the tubular end comes in a variety of bore sizes that vary by 1 mm. It would be highly advantageous and economical to simplify fitting the breast shield over a mother's breast by altering the tubular end of the breast shield.